Knitting machine



March 5, 1957 Filed Oct. 7, 1955 R. H. LAWSON KNITTING MACHINE 3 Sheets-Sheet 1 FIG. 2.

' INVENTOR.

ROBERT H. LAWSON ATTORNEYS March 5, 1957 Filed Oct. 7, 1953 3 Sheets-Sheet 2 j], ll8 l 82 FIG. 5.

FIG. 3.

|44 INVENTOR. ROYBERT H. LAWSON ATTORNEYS March 5, 1957 R. H. LAWSON 2,

KNITTING MACHINE Filed Oct. 7, 1953 3 Sheets-Sheet 3 INVENTOR. ROBERT H. LAWSON ATTORNEYS nited KNITTING MACHINE Application October 7, 1953, Serial No. 384,612

9 Claims. (Cl. 66-149) This invention relates to knitting machines and has particular reference to take-up means involved in'the production of stockings and particularly those of fine gauge. The invention relates to take-up means of the general type disclosed in my application Serial No. 207,- 075, filed January 22, 1951, now Patent No. 2,709,352 and in my Patent No. 2,625,026, datedlanuary 13, 1953.

' Individual separate stockings may be knit starting with bare needles in accordance with the procedure and utilizing such instrumentalities as are disclosed in the patent to R. W. Scott No. 1,282,958, dated October 29, 1918. In accordance with this procedure, which need not be repeated herein in detail, a nonravelling selvage is first produced and thereupon loops are received on the transfer elements by projecting them between alternate needles, thus to receive and hold the initial courses during the knitting of a hem'or welt, there being produced in the formation of this welt a sufiicient number of courses to secure the desired length thereof. At the completion of the welt, the loops which were held by the transfer elements are returned to the needles and knitting is resumed tying the welt loops into loops at the beginning of the leg so that a doubled or inturned welt is produced. The welt fold as it is being formed and thereafter has generally been carried away from the needles to a considerable extent by gravity receiving initial assistance from a presser such as shown in said Scott patent. The foregoing method has been quite satisfactory but it has been recognized that more uniform and perfect stitches might be formed if the fabric being knitted were made to fall away from the needles more readily and the welt prevented from twisting inside the needle cylinder. Furthermore, more satisfactory results would be obtained if a tension could be applied substantially throughout the knitting of the fabric following the welt.

When stockings are being produced in the form of a continuous string, tension may be applied to the fabric through the use of take-up rolls which maybe caused to stop or to advance at varying speeds as determined by control mechanism, thus to apply a uniform but variable tension to the fabric. The use of an arrangement such as just indicated requires, however, that the stockings should be knit in a continuous string 'joined, for example, by a yarn having sufficient strength for knitting and providing a connection between successive-stockings, but frail enough to permit the various finished stockings to be torn apart or separated. However, if the stockings are to be knit separately so that each stocking is begun on bare needles, it will be evident that take-up rolls cannot be used. v

; Said, prior application Ser. No. 207,075 disclosesa method and means whereby during-knitting proper tension'may be applied to stockings when they are knit separately and individually. In particular, theinvention is of importance as applied to the knitting of sheer ladies hosiery, for example on a 400 needle machine. In the case of sheer hosiery of this type the maintenance of proper tension during the knitting of the leg is particularly important, If the tension is not maintained uniform, there are likely to be produced shadow areas, streaks, or

2,783,630 i Patented Mar. 5, 1957;

- regions having the appearance of being scratched. If,

on the other hand, a uniform tension is provided during knitting of the sheer leg fabric, these irregularities are substantially reduced or eliminated and stockings of acceptable appearance may be uniformly produced. In accordance with said application, therefore, tension is applied during the leg and foot knitting by the provision of a take-up device which grabs the welt of the stocking and pulls the leg and instep portions of the stocking uniformly downwardly under gravity action during the progress of the knitting. After the loopers rounds are completed the stockingis dropped fromthe needles, the take-up is released from the welt and the stocking may be blown by a blast of air transversely into a suitable receptacle. Simultaneously the knitting of a subsequent stocking may be begun on bare needles as indicated above.

My Patent No. 2,625,026 referred to above relates to a stop motion which is arranged to detect the proper re-' moval of a stocking from the take-up. As will become apparent hereafter, the stocking removing means and'the stop motion of said patent may be applied to a machine embodying the present invention.

It is the general object of the present invention to provide a take-up means of the general type referred to above which, in particular, is adapted to seize a stocking during a pause in the knitting thereof. Furthermore, in accordance with the present invention, the positioning of the take-up stocking grasping device is effected during cessation of the knitting. Usually, all operations'a'ssociated with a knitting machine are dependent upon the motions associated with knitting or, at least, rotation of the cylinder or cylinders in a circular knitting machine. In accordance with the present invention, provision is made for the occurrence of auxiliary operations while the needle cylinder is stationary.

The foregoing objects of the invention and otherobjects particularly relating to details of construction and operation will becomeapparent from the following description, read in conjunction with the accompanying drawings, in which:

Figure 1 is a fragmentary front elevation of a circular knitting machine embodying the invention, this figure particularly showing the left-hand side of the machine;

Figure 2 is a similar view but showing the right-hand side of the machine; p

Figure 3 is a left-hand side elevation showing various elements of the machine in section;

Figure 4 is a fragmentary right-hand elevation showing various elements of the machine particularly illustrated in Figure 2; and

Figure 5 is a Wiring diagram showing certain electrical connections involved in the operation of the machine.

The basic elements of the knitting machine shown herein are disclosed in detail in my application and patent referred to above and in the Scott Patent No. 1,282,958, to which reference has been made. Accordingly, there are illustrated and described herein only such parts of the basic knitting machine as will serve to make clear the operations which are novel. I p

The needle cylinderillustrated at 2 is slotted to carry needles 4 with which cooperate conventional sinkers (not shown). A' rotary dial 8 carries transfer elements 10 of the type described in said Scott patent. A stationary dial cap is provided with cams which in conventional fashion operate the transfer elements 10 as the dial 8 and the needle cylinder 2 rotate. The dial 8 is provided with a series of openings peripherally arranged so as to be brought during rotation successively in alignment with a vertically directed tube which, atproper'times during 1 operation, receives, air through connection. 16 to direct a blast through the openings, the blast being caused to be greases intermittent-by reason of the interruptions afforded by portions of the dial between the openings. Additional intermittent characteristics of operation of the air blast are imparted by control of the air supply so that the air flow occurs only during'certain courses in the knitting of the turned welt, for example, being supplied through two courses, turned otf through a series of succeeding courses, for example-two, and then turned on again for a repetition of the air supply cycle.

Relative movements of conventional character are impatted to the various instrumentalities in conventional fashion, and the particular driving and controlling means need not, therefore, be described. As is usual in knitting machines of this general type, yarns are selectively fed from ya'rn fingers 20 under the control of push rods 22 moved in response to cams on the main cam drum 23 of the machine.

There is frictionally held by screws snugly within the needle cylinder of the machine a cylinder 24 having an outwardly flared upper portion to guide smoothly inwardly the portions of the fabric being lrnitand, particularly, the fabric forming the welt. In the case of the present machine, this cylinder 24 is provided with a smooth interior and its lower edge is bevelled to receive the grab take-up as will be hereafter described. The upper portion of the interior of cylinder 24 is conically convergent downwardly to deflect the air inwardly.

. A cylindrical cup 28 is carried by a bearing 30 mounted at the upper end of a tube 32 which passes slidably down? wardly through openings in a carriage 34. A spring 38 is under compression and normally urges the sleeve 32 upwardly with respect to the carriage. Guide tracks 40 are embraced by the carriage, and these tracks are supported by screws and spacers indicated at 42 from the conventional cylinder raising tube 44 which is fixed against rotation but which is adapted for axial movements to produce through a ball race arrangement 59 and pins 52 axial movements of the needle cylinder for the purpose of adjusting the lengths of stitches drawn by the needles by'producing relative movement between the needle cylinder and the needle actuating cams. These axial movements which are of slight extent are Produc d by en a m with a bra ke 4.6 carrie by the cylinder raising tube 44 of the portion 48 of a lever acted upon by cams on the main cam drum of the machine.

1 The tube 32 has fixed to it a member 54 which is held against rotation by :sliding interengagernent with the carriage 34. A Bowden wire 58 secured to the member se t p r i to r l a stocki s escrib in my said application. This Bowden wire is actuated by cams on .the main cam drum of the machine.

A rod 62 is secured at its lower endin the carriage 34 and extends upwardly through tube 32 supporting through a suitable self-aligning joint connection .65 a clamp member 66 which is arranged to clamp between a flange. thereof and a shoulder in the interior oi the rl he e of th lt of a o king- The p 25 is provided with a series of openings for the downward flow of air therethrough.

A cable 74 is secured to an arm 76 of the carriage 3A and is trained about pulleys 78 carried byla bracket 80 secured to the cylinder raising tube 44 and thence extends to a winding drum 82 to which its end is fastened.

All o th p r s h ret f f r d t re dis lo d n reater d ta l in my appl ca ion. a d p en e rr d to a o e o her i other parts hi hr nay bod ed n t p e ent m ch eh p e n n on relates primarily to the control of the cable 14, and, in particular, to its control. during periods of stationary condition of the needle cylinder. The controls for the cable involved in mysaid application and patent have, thereforegsubstituted for them other controlling means embodyingihe'present invention. I At-IQ J; and 88 there are, respectively, illustrated the idle, low speed and high speed'pulleys serving for operation of the machine, the low and high speed pulleys being connected to conventional driving gearing for the purpose of imparting rotary and reciprocatory movements to the needle cylinder and dial and also movements to the conventional main chain (not shown) and the main cam drum 23.

In accordance with the present invention, the idle pulley 84 has secured thereto a sprocket 90 which, through a chain 92, serves to drive a sprocket 94 secured to a shaft 96 which is suitably mounted in the machine and conv ni ntly e ends t r u h a hollow shaf on which the main cam drum 23 is mounted. The shaft 96 has mounted thereon an eccentric 98 the strap of which is in the form of a pawl 100 which is arranged to engage spaced teeth 102 and 109 in the periphery of the conventional speed change drum 104 which is geared to the main cam drum and carries cams (not shown) for effecting shifting of the driving belt 11(1 through the belt shipper 108 between the low speed and high speed pulleys 86 and 88. In accordance with the present invention, there are provided additional cams 166 and 107 Serving tomove the shipper 108 to an extent necessary to. shift the belt 110 to the idle pulley 84 during autqmatic operation of the machine.

A slide 112 ismjounted for vertical movement in a fixed bracket and its lower end extends laterally as indicated a H and; c nn c ed. t he P unger no of a ol no d .1 Whish, when energ zed, serves to move the s ide d nwa dly No mally, t s ide is uned up: ardly by the ad eu t a spri g 7 .29 he e itist-12 Carries ati s uppe d. a la ral y x ding p n L22 hi nderlies t e p w 1- 0- The ac on of. spr n 129 norm ll held th pawl 1. 0. in upper po ition s t a it may ci o te -haw en em n w h h rum 104.

pair 0f am discs .2 and .6 a se ur d ta the pee change drum 104 and a ran ed e' actu t switches 128 and 130, respectively, through the medium of cam projections 132 and 134.

T th le ehan en of s aft 96 re i ecured he dr n e m nt o n le trom tic clu c 136, the n'element at whic is c nne ted r h sh f 1&8 m a sp c 1 0 Which, t rou a c a 42 driv s a sprocket 144 secured to a shaft 146. The shaft 146 carries a pinion 148 which meshes with an associated Pinion .1 0 ecu ed o a shaft .152 on which sha t there is secured he cable drum 8 pr ous y mention Id- A second drum 154 of smaller diameter than the drum $2 is secured tattle s ft 5 and has e r to n wound about it, a cable 156 which supports a count eigh 1.58. The co nt e t 1,58 s'So c n as o provide a suitable tension on the stocking during knitting iereo'f- A pitiifialfifl carried by the sh ft 15 meshes w t a gear 1 moun d on a sh Sha t which also car i s a pai of cam d c .164 a d .6.6 h in ob h sk an be n the" pioneers 9f pa r of swi ch 1.68 an 70, es ecti el a A d ten le er 17 pivo ed t the ma hi e f ame a 174 and s norm ll ur d c unte c i e, s i ed n' i'g r 3Jby spr ng e din to m t u s lri tion 178' between' 'teeth ofthe gear 162. The lever 172 is n e by a ink 0 o th Pl g f a o enoid 1'82 which, when energized, serves to remove the detc'nt e 1 f om eng em nt th gea 16 ?Il upp end of lever 17 2 is provided with a follower engage'able by ,a earn 171 on the main cam drum, which cam has lobes 171A, 171B and'1716 to which reference will be made hereafter,

- Referring to Figurefi, there are shown therein the various electrical connections involved which, in addition to the yarious elerne'nts already-mentioned include the delay relay;'- 184;themaster switc'li 186,-,and a rectifier 188 which serves to provide from the alternating current supply direct current for control of the electromagnetic 'clutch 136. Details of the electrical connections will be apparent hereafter from description of the operation of the entire machine.

The operation of the described mechanism may be best understood by considering the sequence of events starting with the discharge of a completed stocking from the grabbing mechanism as in my application and patent referred to above. The next step of the cam drum 23 causes a movement of the speed change drum 104 to move cam 166 to position to shift the belt 110 to the idle pulley 84. During this movement, the cam 132 closes the normally open switch 128.

The result is the beginning of rotation of the shaft 96 by its connection to idle pulley 84 and the energization of clutch 136 to couple shaft 96 to shaft 138. The energization of the clutch is effected through the master switch 186, which is closed throughout operation of the knitting machine, the closure of switch 128, as just mentioned, and the normal position of switch 170 making the lefthand contact illustrated in Figure 5. Rectifier 188 provides direct current to the energizing coil of the clutch from the alternating current supply line. As will be noted from the drawings, there is a speed reduction between sprockets 90 and 94 and a further speed reduction through pinion 148 and gear 158 with the result that the shaft 152 is driven at a lower speed than the idle pulley 84, the speed reduction being conveniently, for example, one to six. The drum 82 is accordingly rotated to raise the carriage 34 and its associated grab elements. At this time, the gear 162 rides under the nose 178 of lever 172 which is free of the lobes of the cam 171 on drum 23, contact between the nose and the gear teeth being maintained by spring 176.

As the carriage 34 approaches its uppermost position, the cup 28 is arrested by engagement of member 54 with the lower race of the hearing at 50 and the clamp 66 continues to rise thereby effecting opening of the grab assembly in the same fashion as described in my prior application and patent. It will be noted that through gearing 160, 162 there is a substantial reduction of speed between shaft 152 and the shaft of gear 162 which carries the cams 164 and 166. As the carriage 34 reaches the upper extreme of its movement, cam 166 acts upon the operating plunger of switch 178 to shift this switch to the righthand position illustrated in Figure 5. This results in immediate deenergization of the clutch 136 so that rotation of the drum 82 is arrested. The drum 82 then becomes released, so far as its drive through clutch 136 is concerned, for rotation under the weight of the grab take-up elements, but reverse rotation is temporarily arrested by engagement of the nose 178 of lever 172 against a tooth of gear 162. It may be noted that clutch 136 is desirably of a known type which may slip without damage even when energized. The cup 28 and clamp 66 are accordingly retained in an upper position with the clamp open and the cup positioned to receive the welt of a stocking.

Inasmuch as swit'ch168 is in the upper position illustrated in Figure 5 at the time switch 178 shifts to its right: hand positiontthough it will have been transiently shifted to its lower position by cam 164 during rise of the take-up elements), the movement of switch 178 to the right-hand position produces energization of solenoid 118. This action permits pawl 188 to drop against the speed change drum 104, and at this time the tooth 192 is in position to be engaged by the end of the pawl so that the rotation of shaft '96 and eccentric 98 efiects a step movement of the speed change drum to remove cam 106 from action upon the belt shipper. The result is that the belt is shifted to the low or high speed pulley (this being controlled by another cam onthe speed change drum), and the rotation of shaft 96 is arrested. As this last mentioned movement of the speed change drum takes place, cam 132 moves to permit opening of switch 128, with the result that'solenoid 11s is'deenergized, despite the location of switch "170th its right-hand position, and pawl 100 is lifted away from;

speed change drum 104.

The knitting machine now operates in conventional fashion, as described in my application and patent, to

start knitting on bare needles and to form and transfer.

of the main chain after transfer advances the speed change shipper.

drum, which in the meanwhile has undergone various intermediate steps of movement'along with the main cam drum, to bring the cam 107 into action upon the belt This results in a shifting of the belt to idle pulley 84 and resumption of rotation of the shaft 96. g In this movement, cam 134 closes switch 130. The closure of switch 131) energizes the coil of the delay relay 184 but this relay does not close its main contacts for a short interval which is sufficient to permit the cylinder of the knitting machine to come to rest. When the main contacts of relay 184 are closed, the solenoid 182 is energized to pull the nose 178 of detent 172 out of engagement with the teeth of gear 162. Carriage 34 is now released to drop, with the result that the clamp 66 closes upon the fabric of the turned welt to clamp it to the upper edge of the cup 28. Tension is thus applied to the fabric. When this grabbing of the fabric takes place, the carriage 34 has a substantial movement downwardly with successive results as follows:

The movement of cam 166 accompanying rotation of the drum 82 during the grabbing movement of carriage 34- permits switch 179 to move to its left-hand positionin Figure 5. However, since switch 128 is open, there is no resulting energization of clutch 136. As the carriage 34 further drops in its fabric grabbing movement, cam 164 acts upon switch 168 to move it to the lower position illus trated in Figure 5. Since relay 184 is closed, the solenoid 118 is energized to permit the pawl to drop to position 'to engage the tooth 189 of the speed change drum and provide an advance step of this drum. The result is removal of cam 187 from action upon the belttshipp'er with the result that the belt is shifted to the low speed pulley and knitting operation is resumed.

Upon the next move of the speed change drum 164,, which immediately follows the resumption of knitting, the cam 134 releases switch 138 to permit it to open.- Both solenoids 118 and 182 are then deenergized "with the result that pawl 188 is moved upwardly by the action of spring 120, and solenoid 182 releases the detent 172.. However, atthis time, the lobe 171A of cam 171 on drum 23, by reason of the last movement of the drum, underlies the upper end of the detent 172 with the result that the detent is held out of engagement with the teeth of,"

gear 162.

The special mechanism to which this application relates? has then been restored to initial condition and remains inactivewhile operation of the knitting machine proceeds as described in said application and patent. The leg or the stocking is knit, with the take-up imparting a proper tension during the knitting. as determined by the weight detent 172 from action by cam lobe 171B duringthe knitting of the foot, but tension is again interrupted at or immediately prior to the knitting of the toe by the release of the detent by cam lobe 1713. At the com-.

pletion of the stocking, the stitches are pressed off the needles during the continued interruption of tensioning, this being desirable to permit the stitches to drop off the needles in clean fashion since tensioning might cause thelast stitch to fall between the sinkers before being eas on, hus pre enting e stll and causing aravell n condi onnsnie liat l-y afte ec nplet on at cast off lever 172 is acted upon by lobe 171C and the take-up drops to i s lo est Pe t en wh eup n i is ensued and th sto king is di a ge by a a blast in the fashion descr b part cu arly n my P ten eferred to above. there being present the stop motion devices of said patent to. effect stopp of the mach in the. e ent. of impr p discharge. The cycle of operation is then repeated be,- sinn ng wi h he nv ine of t e cam lies t sh ft the belt 110 to the idle pulley,

il e no e ha in a cordance wit heabeve there ar obta n d t e anta s f posi io ing t e stabbin mechani m n of ca s ng t e ctu l abbing t ake Pla at im n. h kn t n operation is interrupt the needle cylinder being stationary. in order to accomplish this, it is necessary to obtain movements of the operating parts of the take-up mechanism while the needle y in er an ass c ated parts a e s ationa y. and or his reason use is made of the rotation of; the idle pulley 84..

I Will be Clear a e nd o th inv ntion may be t a ned in io s er ay and it the etcre. to be understood that the invention is not to be regarded as limited except as required by the following claims. It will, for example, be evident that, if desired, he motion of shaft 96, or its equivalent, may be secured from a separate motor, rather than from an idle pulley, the separate motor being energized at times corresponding to those of shift of the belt to the idle pulley. The last type of; operation may be used when a main variable speed motor is used for drive eliminating necessity for the use of a belt and multispeed pulley drives.

What is claimed is:

1. An automatic article tensioning device for a circular knitting machine having a needle cylinder and adapted to knit separate articles each of which is pressed off when completed, comprising vertically movable article grasping means, and automatic controlling means for effecting in sequence raising of said article grasping means while knitting is interrupted, grasping of1the initial portion of an article by said article grasping means, and downward movement of said article grasping means while it grasps the article to impart tension to the article during continued knitting thereof, said controlling means effecting automatic resumption of knitting following said interruption thereof.

2. An automatic article tensioning device for a circular knitting machine having a needle cylinder and: adapted to knit separate articles each of which is pressed off when completed, comprising vertically movable article graspa irig means, and automatic controlling means for effecting n sequence raising of said article grasping means, graspmg of the initial portion of an article by said article grasping means while knitting is interrupted, and downward movement of said article grasping means while it grasps the article to impart tension to the article during continued knitting thereof, said controlling means effecting automatic resumption of knitting following said; intcrruption thereof.

d. An automatic article tensioningdevice for a circular knitting machine having a needle cylinder and adapted to knit separate articles each of which is pressed off when completed, comprising vertically movable article graspng means, and automatic controlling means for effecting in sequence raising of said article grasping means while knitting is interrupted, grasping of the initial portion of an article by said article grasping means while knitting is interrupted, and downward movement of said article grasping means while it grasps the article to impart tension to the article during continued knitting thereof, said controlling means effecting automatic resumption of knitting following said interruption thereof.

4. An automatic article tensioning device for a circular knitting machine having a rotating needle, cylinder and adapted to knit separate articles each; of which is pressed ll hen cenuale ed, compri ng ertical y movable article aspin ean and automatic. controlling means for fiee in sequen e. raising f said articl raspin means while said needle cylinder is stationary, grasping of the initial portion of an article by said article grasping means, and downward movement of said article grasping means while it grasps the article to impart tension to the article during continued knitting thereof, said controlling means eifecting automatic resumption of knitting following said stationary condition of the needle cylinder,

5. An automatic article tensioning device for a circua kni i g m chi ha a rota g edle cy nd r and adapted to knit separate articles each of which is pressed off when completed, comprising vertically movable article grasping means, and automatic controlling means for effecting in sequence raising of said article grasping means, grasping of the initial portion of an article by said articlc grasping means while said needle cylinder is stationary, and downward movement of said article grasping means while it grasps the article, to impart tension to the article during continued knitting thereof, said controlling means effecting automatic resumption of knitting following said stationary condition of the needle cylinder.

6. An automatic article tensioning device for a circular knitting machine having a rotating needle cylinder and adapted to knit separate articles each of which is pressed off when completed, comprising vertically movable article grasping means, and automatic controlling means for effecting in sequence raising of said article grasping means while said needle cylinder is stationary, grasping of the initial portion of an article by said article grasping means while said needle cylinder is stationary, and downward movement; of said article grasping means while it grasps the article to impart tension to the article during continned knitting thereof, said controlling means effecting automatic, resumption of knitting following said stationary condition of the needle cylinder.

7. In a circular knitting machine having a needle cylinder and adapted to knit separate articles each of which is pressed off when completed, means for automatically seizing the free end portion of each article during an inter'ruption of the knitting thereof, means for efliecting automatic. resumption of knitting following said interruption, and means for imparting tension to the article during subsequent knitting.

8. In a circular knitting machine having a needle cylinder and adapted to knit separate articles each of which is pressed off when completed, vertically movable article grasping means, automatic meansv for raising said article grasping means to position tov receive the initial portion of an article while knitting is, interrupted, means for then automatically elfecting knitting of an initial portion of an article and its location within said article grasping means, means for then automatically effecting grasping of said initial portion of the article, and means for then automatically effecting downward movement of said atticle grasping means to impart tension to the article during continued knitting thereof.

n. i c l r kni ti g machine having a ne d e ylinder and adapted to knit separate articles each of which is pressed off when completed, vertically movable article grasping means, automatic means for raising said article grasping means to position to receive the initial portion of an article while knitting is interrupted, means for then automatically effecting knitting of an initial portion of an article and its location within said article grasping means, means for then automatically effecting grasping of said initial portion of the article while knitting is interrupted, and means for then automatically effecting downward movement of said article grasping means to impart tension to the article during continued knitting thereof.

References Cited in the lie of this patent UNITED STATES. PATENTS 2,230,974 Gagne. .7, Feb. 4, 194-1 

